A jet plane is flying at a constant altitude. At time t1=0t 1=0, it has components of velocity vx=90m/s, vy=110m/sv x = 90m/s, v y=110m/s. At time t2=30.0st 2=30.0s, the components are vx=−170m/s, vy=40m/sv x =−170m/s, v y=40m/s. (a) Sketch the velocity vectors at t1and t2.
How do these two vectors differ? For this time interval calculate
(b) the components of the average acceleration, and
(c) the magnitude and direction of the average acceleration.

The average acceleration over some time interval is equal to the ratio of the change in velocity over the duration of the interval , or

which can be split into the and components as

The magnitude of this average acceleration is

and its direction is such that

which corresponds to a direction of about 15.1º South of West.

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia